Why? Tradition...

"The core methods of kenjutsu are those of a weapon long disused, and one of the primary reasons we practice kenjutsu is the idea that we are forging a link in an unbroken chain; a chain that runs backward in time for hundreds or thousands of years.

At the front of that chain is an anchor rooted in tradition, and at the end of that chain we stand. With that chain at our back we can face forward into the future without being swept away by the rushing tide of history and change. Break it, and we are lost."